Along with Eric Blumenfeld, Parkway Corporation has become one of the most important developers along the North Broad Street corridor. And like Blumenfeld, Parkway sees the street as having untapped potential as an all-day live/work/play environment. (The folks at Parkway should know: the company headquarters is at Broad and Race streets.)

What’s different about Parkway’s latest development proposal is that it seeks to combine all three of those elements into a single package at a convenient location.

“It’s my dream to build significant office space there, to get some jobs into that neighborhood,” said Parkway CEO Robert Zuritsky. “The retail and residential are a slam dunk, but [North Broad] is also an important commercial district.”

Parkway already has twin residential/retail complexes under construction two blocks to the south of this site, at Broad and Callowhill streets. The Hanover North Broad project “will be fantastic,” Zuritsky said, and it builds on similar activity taking place around it. Zuritsky pointed to fellow developer Craig Grossman, who got his start working with Midtown Village transformer Tony Goldman, as one of the other catalysts in the Callowhill district who is quietly acquiring properties with the intent of creating similar results in the vicinity of the Rail Park.

To date, however, none of the projects have incorporated office space.

It’s not that the area lacks for employment: the School District of Philadelphia, the Community College of Philadelphia and 1500 Spring Garden are all major employment hubs adjacent to this project. What it lacks is the sort of all-inclusive package found in projects like East Market.

“The office space is the first driver of this project,” Zuritsky said.

That’s apparent from the design of the project as well: the office tower is the larger of the two buildings in the BLTa-designed complex.

BLTa principal Michael Prifti echoed Zuritsky in his assessment of North Broad’s strength and potential.

“There’s already significant development at this intersection,” he said. Blumenfeld turned the former Thaddeus Stevens School of Practice just off the northeast corner into a luxury apartment building called Mural Lofts and plans to build a retail structure on the vacant corner lot next to it, and Bart Blatstein converted the old Philadelphia State Office Building into another luxury apartment tower, Tower Place. (Plans to add a retail structure to its plaza are on indefinite hold.)

Prifti noted the intersection had other positives: “It’s so transit-oriented,” he said, adding that the potential existed for a direct concourse connection between the new Parkway development and Spring Garden station on the Broad Street Line. “Temple is nearby with a very robust presence, and it’s growing to the south.

“It’s actually a very hot corridor, and this building is at the center of it all.”

The development consists of a 13-story, 140-foot-tall residential tower with a parapet that slopes to the west at the top to shield the rooftop terrace from the 20-story, 330-foot office tower to its east. That tower is similar in massing to the firm’s initial East Market tower, with a slender tower perched atop a four-story podium containing two levels of retail and two of office space, with an office amenity level atop the podium.

The office tower’s design, however, is a significant departure from BLTa’s usual work: an all-glass slab whose service core is attached to its western end. The slab itself is distinguished by alternating two-story bands of beveled and flat glass panels that also cover the tower’s exoskeleton of columns and diagonal bracing, both necessary in order to produce large, column-free floorplates.

Though the design gives the tower the feel of a giant co-working space, it is not designed with that purpose in mind. As with the new Comcast Innovation Center, the tower is designed to encourage both clustering and cooperation between units of an organization, a function that can be enhanced by interior stairwells between floors within a pair.

The building is the glassiest structure BLTa has yet produced, and lead designer Milton Lau said that its location encouraged some outside-the-box thinking. “Although the building’s in Center City, it’s on the periphery that we feel freedom to break away from context,” he said. In fact, the lack of context — no structures abut it, and the intersection it sits on is awash in open space — “gives it the opportunity to act as a prism that captures the light and sky.”

The design also gives the building a great amount of flexibility that will allow it to be configured to suit a wide range of possible tenants.

That’s good for Parkway, which has not yet identified a lead office tenant. And while Zuritsky is in search of office tenants for this speculative building, he said that if none are found, it won’t sink the project: “If we can’t make it office, we’ll do residential.”